The subject-matter of the present invention is a method of retaining and operating an inserter of an intrauterine contraceptive device.
Further subject-matter of the invention is an inserter of an intrauterine contraceptive device (hereinafter IUCD) for the application of this method.
Methods and devices for inserting IUCDs, and especially IUCDs the cooperation of which with an insertion needle is maintained by a pull thread are known, for example from patent EU 0 160 633, in FIGS. 12 and 13 of which such a device is illustrated. In it the pull thread is retained simply by folding it beyond the proximal edge of the inserter. Such an embodiment does not permit the formation of single-use inserters provided at the outset with an IUCD retained on the needle in a reliable manner and forming a sterile assembly ready for use.
To this end, it has already been proposed in EU 0 191 747 to provide a retaining element for the pull thread in the form of a slit, as well as a blocking device releasable from the sheath on the needle. However, the method of operating this inserter requires that the blocking of the thread and of the sheath are released separately, which firstly carries the risk that the cooperation of the IUCD and the needle might be broken in the course of manipulation and in the course of operating the inserter, before the insertion of the element retaining the IUCD in the wall of the uterus has been completed, and, secondly, makes it difficult to operate said device with one hand, and, furthermore, once the operation of the inserter has been completed this method carries the risk that the pull thread will be pinched between the needle and the sheath, resulting in the exertion of traction on the IUCD when the extractor is withdrawn.
The present invention aims to remedy these disadvantages and, above all, to simplify the procedure of operating the inserter in order to allow easy release of the pull thread without risk of breaking the cooperation between needle and IUCD.
Advantageous embodiments of the method according to the invention which, in particular, firstly ensure effective retention of the pull thread and secondly allow complete release of the latter, also after operation of the inserter, are the subject-matter of the invention.
The invention also aims to provide an inserter allowing the method according to the invention to be implemented. The specific features of the inserter permitting implementation of this method are the subject-matter of the invention.